🎣 Species Targeting Guide: Flathead Catfish¶

Scientific name: Pylodictis olivaris Also known as: Mud cat, shovelhead cat, yellow cat, pied cat Guide last updated: 2026-05-24 Author / source: Maryland Fishing Guides

1. Species Overview¶

Field	Details
Family	Ictaluridae
Typical size	18–36 inches / 5–20 lb in Maryland; commonly caught 8–15 lb
Trophy size	30 lb+ is a notable fish; 50 lb+ flatheads are possible in the lower Susquehanna
Average lifespan	20+ years; a 30 lb fish may be 15–20 years old
Water type	Freshwater
Native range	Mississippi River basin and Gulf Coast drainages; introduced (invasive) in Atlantic drainages including the Chesapeake Bay watershed
Conservation status	INVASIVE in Maryland — not native to Atlantic drainages; harvest is actively encouraged by MD DNR

Identifying features: Large, distinctly flattened head with a wide, shovel-shaped profile — the most reliable field mark. Lower jaw protrudes noticeably beyond the upper jaw (the opposite of channel and blue catfish). Body is mottled with irregular blotches of yellow-brown, olive, and dark brown on a yellowish-tan background — no uniform coloration. The tail is slightly notched but not deeply forked (unlike blue catfish). Eyes are small and positioned on top of the flat head. Adipose fin is present. Can reach enormous size; young fish under 8 inches may be confused with bullheads but the flat head and protruding lower jaw distinguish them.

Easily confused with: Blue catfish (Ictalurus furcatus) — deeply forked tail, uniform blue-gray coloration, shorter head, upper jaw longer than lower; blue cats also scavenge cut bait freely while flatheads strongly prefer live prey. Channel catfish (Ictalurus punctatus) — deeply forked tail, spotted sides on young fish, rounded and less flattened head, upper jaw longer than lower. Bullheads (Ameiurus spp.) — much smaller, square or rounded tail, no protruding lower jaw. The combination of flat head + protruding lower jaw + mottled yellow-brown coloration is unique to flatheads.

2. Habitat & Where to Find Them¶

Preferred structure: Deep holes adjacent to heavy woody debris — root wads, log jams, sunken timber, and brush piles are the single most important habitat feature; undercut limestone or clay banks; large boulders and ledge faces in the Susquehanna River; deep slow pools directly downstream of rapids or riffles where current breaks create a slack-water refuge
Depth range: Typically 8–25 feet in river channels during the day; move to shallower flats and shoreline cover at night to feed; in winter, hold in the deepest available holes (20–40+ feet in the lower Susquehanna)
Water temperature range: Most active at 65–80°F (18–27°C); feeding slows significantly below 50°F (10°C); near-dormant in deep holes below 45°F; peak feeding is in the warmest months, June through early October
Water clarity preference: Tolerant of turbid, stained, and murky water; the Susquehanna often carries heavy silt load especially after rain — flatheads use lateral line and barbels to hunt by vibration and smell rather than vision; prefer slightly turbid to murky water over gin-clear conditions
Current / flow: Strong preference for current breaks — the seam between fast and slow water is a prime holding location; eddy lines behind large boulders; the inside of river bends; deep troughs that shelter fish from the main current; direct heavy current is generally avoided for holding, but they travel the margins of current seams at night
Cover & ambush points: Log jams and root wads are the quintessential flathead hideout; boulder faces; bridge support riprap; dark undercut banks; any large woody debris accumulation in 8–20 feet of water; the downstream tails of deep pools where current slows
Bottom composition: Mixed sand, gravel, and cobble with clay or mud banks; boulder substrate in the Susquehanna; heavily favors areas where hard substrate meets softer mud near wood debris

Local hotspots / GPS marks: The lower Susquehanna River from Conowingo Dam (Harford/Cecil counties) downstream to Havre de Grace and the upper Chesapeake flats is the primary Maryland flathead fishery; Conowingo Pool (the impoundment above Conowingo Dam) holds a substantial population; the Susquehanna below the dam to the bay offers excellent access from bank and boat; to a lesser extent flatheads have been documented in the Patuxent River and potentially other Piedmont tributaries — confirm current MD DNR distribution data as the population continues to expand.

3. Seasonal Patterns¶

Season	Behaviour	Location	Best tactic
Spring	Metabolism rising as water warms above 55°F; pre-spawn feeding begins in earnest by May; fish move from deep winter holes to mid-depth cover	Deep pool edges, log jams, and rock faces as water approaches 60°F	Live bait on a three-way rig near deep structure; night fishing begins to produce by late May
Summer	Peak activity — spawn occurs when water reaches 70–75°F (June–July); post-spawn fish feed heavily through August; night fishing is the primary strategy	Active feeding on shallow flats and shoreline cover at night; retreat to deep holes and woody debris by day	Night fishing with large live baits (sunfish, big shiners, bullheads) near log jams and undercut banks; fish deep slack-water holes during the day
Autumn	Excellent fishing through September and October as fish feed heavily before winter slow-down; fish become more predictable in their deep holding areas	Deep pool tails, large log jams, and river bends; shallower than in winter	Live or fresh-dead bait fished near bottom in known deep holes; fish can be contacted day or night more readily than summer
Winter	Near-dormant in the deepest available holes; feeding very infrequent; fish tightly packed in log jams and deep boulders	The deepest holes in Conowingo Pool and the lower Susquehanna channel, 20–40+ feet	Not a productive season; if targeting, fish the warmest part of the day with a small live bait directly on bottom in the deepest accessible hole; very slow technique required

Spawning season: June through early July in Maryland when water temperatures reach 70–75°F; males excavate and guard nest cavities under logs, rocks, and in undercut banks; avoid heavily disturbing known spawning areas; catch-and-release is encouraged during the spawn, and fish released near nests should be handled quickly to allow the male to return to guarding
Peak feeding windows: Late May through early June (pre-spawn feed-up), late July through September (post-spawn recovery and fall feed), and especially August–October when fish are aggressively preparing for winter; the prime time is any warm, overcast night from June through October

4. Timing & Conditions¶

Time of day: Night fishing is far and away the most productive approach — flatheads are crepuscular to nocturnal predators; the best window is typically 30 minutes after sunset through midnight; fish transition from deep daytime cover to shallow feeding areas as darkness falls; a second movement occurs just before dawn; daytime fishing in deep holes can produce but requires patience
Tide (if applicable): Tidal influence is felt in the lower Susquehanna and Havre de Grace area; an incoming tide and the associated movement of baitfish up into shallower areas can concentrate feeding activity near the river mouth; less of a factor in Conowingo Pool and the upper river
Moon phase: New moon and dark nights are traditionally considered prime flathead nights — less ambient light keeps fish out of deep cover longer and on the feed in shallow areas; full moon nights can still produce but fish may retreat to cover earlier
Barometric pressure: Stable or slowly falling pressure typically produces the best night action; a rapidly dropping barometer ahead of a major storm can trigger a brief feeding frenzy, then activity drops off; stable summer high-pressure systems with warm nights are ideal
Weather triggers: Warm, overcast, humid summer nights are the gold standard; a warm rain event that slightly raises river levels and colors the water can trigger excellent feeding activity; avoid fishing during or immediately after major flood events when current velocity makes presentation impossible and fish scatter; a period of stable warm weather following a cold spell will bring fish back on the feed
Light conditions: Darkness is the most important light condition for shallow-water feeding; heavy cloud cover amplifies nocturnal activity; on rare clear full-moon nights, flatheads may stay deeper — fish near the bottom of the main river channel rather than shallow structure in these conditions

5. Diet & Feeding Behaviour¶

Natural prey: Strongly prefers LIVE fish above all other prey — this distinguishes flatheads from channel and blue catfish; primary forage in Maryland includes gizzard shad, American shad and hickory shad (especially below Conowingo Dam), white suckers, fallfish, golden shiners, river chubs, and sunfish species (bluegill, green sunfish, pumpkinseed); will also take crayfish, large hellgrammites, and occasionally bullheads; in the Susquehanna, American eels are a natural part of the diet
Feeding style: Ambush predator with significant active hunting at night — not purely stationary like some catfish; moves out of deep daytime cover to patrol gravel bars, boulder fields, and shoreline structure after dark; uses highly sensitive barbels, lateral line, and olfaction to locate prey in zero-visibility conditions; strikes suddenly and engulfs prey whole; does not typically scavenge carrion unlike blue and channel catfish
Seasonal forage shifts: Spring — primarily shiners, suckers, and fallfish; Summer — shad, sunfish, and whatever is most abundant; Fall — feeding heavily on available forage before winter; flatheads below Conowingo Dam have excellent access to migratory shad runs in spring, making them particularly well-fed and large
Match-the-hatch notes: The most important concept for flathead fishing in Maryland — present a LIVE bait that matches the forage in the immediate water; below Conowingo Dam, a live 8–10 inch gizzard shad is arguably the single best bait available; in Conowingo Pool, live bullheads and large shiners are proven; size matters — a 6–12 inch live bait is appropriate for targeting large fish, and don't be afraid to go bigger for trophy flatheads

6. Tackle & Gear¶

Rod¶

Length / power / action: 7'–8' heavy or extra-heavy power, moderate-fast action rod; a stout fiberglass or graphite composite rod with a strong backbone is needed to lever big fish out of heavy timber; medium-fast action allows the fish to take the bait before the angler feels the weight; baitcasting or heavy spinning; some anglers use 8'–9' heavy surf-style rods from bank positions on the Susquehanna for added casting distance

Reel¶

Type & size: Large baitcasting reel (Abu Garcia 6500/7000 series, Penn Squall 20, or equivalent) with a strong, reliable clicker drag for bait-soaking — the clicker allows you to detect runs while the line is free to pay out before the hook-set; alternatively a large spinning reel (5000–8000 size) with 30+ lb braided line for lighter live-bait presentations; a strong clicker/baitrunner feature is a major advantage

Line¶

Main line: 50–65 lb braided main line is the standard for heavy cover and large fish; braid's zero-stretch improves hook penetration on the powerful sweep-set needed against bony catfish mouths; 30–40 lb monofilament is used by some anglers fishing open water near the river mouth
Leader: 40–60 lb monofilament or heavy fluorocarbon leader, 18–36 inches; mono's stretch provides a slight shock buffer when a large fish surges and helps keep live bait lively longer than braid alone; connect to main braid with a quality barrel swivel (size 2/0–3/0)

Terminal tackle¶

Hooks: 8/0–10/0 non-offset circle hooks are the preferred choice — Gamakatsu Octopus Circle, Owner Mutu Circle, or similar; circle hooks dramatically reduce gut-hooking, improve hook-up rates on the delayed flathead bite, and allow easy release of undersized or unwanted fish; some veteran flathead anglers use 7/0–9/0 Kahle hooks for live bait in snaggy cover; avoid treble hooks — they tangle live bait and complicate release
Sinkers / rigs: Three-way swivel rig is the workhorse — tie the main line to one eye, a 12–18 inch dropper to a 2–4 oz bank sinker (or heavier in strong current) on the second eye, and an 18–36 inch leader to the hook on the third eye; this keeps the live bait up off bottom and allows it to swim naturally; slip-sinker (Carolina) rig with a 2–4 oz egg or no-roll sinker above a barrel swivel, 24 inch leader, and circle hook is an excellent alternative in areas with moderate current; for bank fishing in slower water, a simple split-shot rig 18 inches above the hook can be sufficient
Other: Heavy-duty snap swivels and quality barrel swivels are essential — save money elsewhere, not on hardware; rod holders or bank sticks are important for soaking bait overnight; a headlamp with a red-light mode for night fishing; a large rubber-mesh landing net (24"+ basket) for large fish; long-nose pliers and a large hook remover for unhooking safely

7. Baits & Lures¶

Best natural baits¶

Live gizzard shad (6–10 inches) — the premier bait below Conowingo Dam where shad are abundant; hook through the back just behind the dorsal fin or through the lips; devastatingly effective for large flatheads; obtain from cast net in the river immediately before fishing
Live bluegill or green sunfish (4–7 inches) — a top bait system-wide in Conowingo Pool and the upper lower Susquehanna; sunfish are tough on the hook and swim actively, producing vibrations that attract flatheads from distance; CHECK current MD DNR regulations regarding the use of live sunfish as bait before using — regulations on live fish baitfish vary and are subject to change
Live large shiners (4–6 inches) — excellent and widely available from tackle dealers; very active on the hook; use in areas where shad or sunfish are not available or legal; hook through the back
Live bullheads (6–8 inches) — highly durable live bait; their own scent and vibration appeal strongly to flatheads; hook through the back; particularly effective in Conowingo Pool
Large live fallfish or river chubs (5–8 inches) — native prey easily obtained via small hook and light line in the river; a completely natural presentation that is extremely effective
Fresh-dead bait as a secondary option: a freshly killed (not spoiled) large shad or shiner can work when live bait is unavailable, but flatheads show a very strong preference for actively moving, live prey — if you can use live bait, do so

Best artificial lures¶

Lure type	Size / colour	Conditions	Retrieve
Large soft-plastic swimbait (e.g. Keitech, Deps Slide Swimmer)	5–8 inch, shad or sunfish colour	Night fishing along shallow gravel bars and boulder fields; active-fish scenario	Slow, steady swimming retrieve just above bottom; pause near structure
Large paddle-tail jig	4–6 inch paddle tail on a 1–2 oz jig head, white or chartreuse	Probing the downstream face of log jams and large boulders in moderate current	Slow hop-and-drag along bottom; allow extended pauses near cover
Live-bait style crankbait (e.g. large Rapala Original Floater)	5–7 inch, shad or perch pattern	Open river reaches; locating suspended fish near the surface at night	Very slow straight retrieve; pause frequently; primarily a locating tool rather than primary flathead technique
Deep-diving crankbait	4–6 inch, shad pattern; 10–15 ft depth range	Daytime fishing deep channel structure when live bait is not available	Slow to medium steady retrieve; tick the bottom along the edge of the river channel
Note: live and fresh-dead natural baits produce far better results than artificials for flathead catfish in Maryland — artificials are a backup option only	—	—	—

8. Techniques & Presentation¶

Primary techniques: Anchored live-bait fishing near identified structure is the foundational flathead method; anchor the boat upstream of a known log jam, boulder field, or deep hole and present live baits on three-way rigs at different depths and distances from the boat; bank fishing the Susquehanna from accessible public shorelines with rod holders and clicker reels set in free-spool mode is very popular and effective; wade fishing shallower riffles and pool edges at night can locate active feeding fish
Retrieve / action: This is primarily a stationary-bait presentation — cast the live bait to the target zone and allow it to swim naturally under tension from the current; occasionally lift and reposition the bait to cover different areas of a hole; do not retrieve actively; the live bait does the work; if using a three-way rig, slowly drag the rig along bottom by paying out line while anchored, covering a fan of water below the boat
Hook-set: With circle hooks, do NOT swing-set — simply reel down the slack until you feel the weight of the fish and continue to reel with increasing pressure; the circle hook will roll into the corner of the jaw on its own; with Kahle hooks a single firm sweep-set after the fish has taken the bait and moved off is appropriate; the most common mistake is striking too soon — wait for the line to come tight and the fish to move before setting
Fighting the fish: Flatheads fight with powerful, bulldozing runs into the nearest heavy cover — the first run is the most dangerous; apply maximum drag pressure immediately to steer the fish away from the log jam before it can wrap the line; do not give line if at all avoidable in the first 10 seconds; once away from the primary cover, flatheads tire relatively quickly compared to their size; they do not jump; keep the rod bent and maintain steady pressure throughout
Common mistakes to avoid: Using cut or stink bait — flatheads strongly prefer live prey and will rarely take rotten bait the way channel and blue cats will; using too light a hook (a flathead can straighten a light-wire hook on the first run); not fishing at night — daytime flathead fishing produces a fraction of the results of nighttime presentations; not anchoring close enough to the actual structure — live bait needs to be within 2–5 feet of the log jam or boulder, not merely in the general vicinity; using a hook that is too small — go 8/0–10/0 circle

9. Regulations & Ethics¶

⚠️ Always confirm current local regulations before fishing — these change.

Legal size limit: As an invasive species in Maryland, flathead catfish have typically had NO minimum size limit — harvest of all sizes is permitted and encouraged; confirm with MD DNR as regulations can be updated at any time
Bag / possession limit: MD DNR has typically imposed NO daily creel or possession limit on flathead catfish given their invasive status and the desire to reduce the population; anglers are strongly encouraged to harvest as many as they legally can; confirm current rules with MD DNR before fishing
Closed seasons: No closed season has typically applied to flathead catfish in Maryland; they are generally open year-round; always confirm with MD DNR
Licence required: Yes — a valid Maryland Freshwater Fishing License is required for all anglers 16 and older; available at marylanddnr.gov or licensed tackle dealers
Gear restrictions: CRITICAL — transporting live flathead catfish is generally PROHIBITED in Maryland (and most states where they are invasive); do not transport live fish from one water body to another; harvested fish must be killed before transport; additionally, regulations on using live fish (sunfish, bullheads, shad) as bait vary — confirm with MD DNR which live baitfish species are legal for use in specific waters before your trip; check if any size or type of hook restrictions apply on the specific stretch of river you are fishing
Catch & release notes: Given the invasive status, MD DNR encourages harvest rather than release; if you choose to release, wet hands are sufficient for handling, avoid lifting by the lower jaw (use both hands to support the body), and return the fish quickly; flatheads do not have venomous spines but the pectoral and dorsal spines can puncture skin — handle with care

Regulations are subject to change. Always verify current rules at marylanddnr.gov or by calling MD DNR Fisheries Service. Pay special attention to live-bait rules and the prohibition on transporting live invasive species before your trip.

10. Handling, Safety & Eating¶

Handling: Support the full body weight — large flatheads (15+ lb) should not be lifted by the lower jaw alone as this can injure the fish and your wrist; use a cradle grip with one hand under the belly and one hand gripping the body behind the head; the wide flat head makes a natural grip point; a large rubberized landing net makes boat landing much safer; for fish over 20 lb, two-person landing is advisable
Hazards: The pectoral and dorsal spines are stout and sharp — not venomous (unlike saltwater catfish), but a deep puncture wound is painful and prone to infection; "catfished" (spine punctures) are the primary hazard; always keep fingers clear of the spine area; the large bony mouth has small, raspy teeth — not dangerous but uncomfortable; use heavy gloves or a lip grip tool for handling if desired
Best eating?: Yes — flathead catfish is widely considered the finest-eating catfish species; the flesh is firm, white, and mild with a clean flavor that lacks the strong "muddy" taste sometimes associated with channel or blue catfish; smaller fish (5–15 lb) have a slightly more delicate texture; larger fish are equally good but the fillets are thicker; given the invasive status, keeping fish for the table is both legal and ecologically responsible
Preparation: Bleed the fish immediately after harvest by cutting the tail or gills; pack in ice as quickly as possible; the skin is thick and should be removed — use a fillet knife and pliers or a skinning clamp; fillet conventionally along the backbone; the red lateral line meat can be trimmed for a milder flavor; excellent fried (classic cornmeal-coated Southern-style), baked, grilled, or used in Maryland-style fish stew; pairs very well with Old Bay seasoning

11. Notes & References¶

Maryland Department of Natural Resources — Invasive Catfish Information: dnr.maryland.gov (search "invasive catfish")
MD DNR Freshwater Fishing Regulations: marylanddnr.gov/sport/pages/fishingfreshregs.aspx
Conowingo Dam fishing access: PECO/Exelon public fishing areas below and above the dam; Havre de Grace public boat ramp (Tydings Park) for lower Susquehanna access
Susquehanna Flats (near Havre de Grace) — public water; excellent boat access to the lower river and upper Bay flathead habitat
"Flathead Catfish in the Chesapeake Bay Watershed" — MD DNR and U.S. Fish & Wildlife Service have published reports on the spread of invasive catfish; reviewing these helps identify current distribution hotspots
Cline, Steve — "Catfishing: Beyond the Basics" (relevant tactics for live-bait flathead presentation)
Local resources: Susquehanna Fishing Tackle (Port Deposit, MD) and area bait shops near Havre de Grace carry live bait and have current river condition reports; local guide services on the Susquehanna specialize in flathead and blue catfish and are an efficient way to learn the river
Night fishing safety: Always wear a life jacket when night fishing from a boat on the Susquehanna; inform someone of your float plan; carry a headlamp and a charged phone; the Susquehanna has strong current and significant submerged hazards, especially near Conowingo Dam